Rheological and Microstructural Assessment of Complex Bituminous Binders [PPT]

In the past years, the use of liquid additives as bitumen modifiers has increased to enhance or adjust the properties of bitumen for wide range of applications. Their molecular composition and mutual interaction result in a specific phase morphology in the binders. Hence, there is a need to evaluate the phase and interphase framework and physical properties of complex binders. The RILEM Technical Committee 272-PIM ‘Phase and Interphase behaviour of innovative bituminous Materials’, Task Group TG1 investigates the characterization of assessing phase interphase properties of complex bituminous binders. In this framework, three liquid additives have been selected with different viscosity, nature and use. They were blended with base bitumen to achieve similar consistency and the blends were further aged. Physical properties were evaluated through rheology using dynamic shear rheometer (DSR) in a wide range of conditions. The phase morphology was addressed by atomic force microscopy (AFM), differential scanning calorimetry (DSC) techniques. AFM and DSC results, from fresh and aged binders, reveal that each binder display specific phase morphology and glass transition characteristics, manifesting mutual compatibility of the individual binder components. This approach of binder assessment: combining phase characteristics and rheological response can assist material selection to specific applications.